1157: Safety and Tolerability of a Recombinant Zoster Vaccine in Patients with Inflammatory Rheumatic Musculoskeletal Diseases: A Prospective Longitudinal Study over 12 Months

Background/Purpose: Herpes zoster (HZ) is common among older adults, with a lifetime risk of 25%. The risk is particularly increased in individuals with immunosuppression such as those with inflammatory rheumatic musculoskeletal diseases (iRMD). In this population, both the underlying disease and immunomodulatory treatments contribute to higher HZ incidence and severity. While the recombinant zoster vaccine (RZV) is recommended for immunocompromised individuals, data on its real-world safety and tolerability in patients with iRMD are still limited.

Methods: Adult patients with rheumatoid arthritis (RA), axial spondyloarthritis (axSpA), and giant cell arteritis (GCA) who were eligible to receive RZV were prospectively included in this ongoing study. Data on demographics, vaccination status, and iRMD diagnosis were collected at first dose visit (FDV). Disease activity and immunosuppressive treatments were assessed at FDV, second dose visit (SDV) and months 3, 6 and 12. Flares, adverse events (AEs), and zoster breakthrough cases were monitored following RZV administration at SDV and months 3, 6 and 12. AEs were categorized by system organ class (SOC) and measured per dose (%). Localized and systemic AEs, including severe AEs (SAEs) and adverse events of special interests (AESIs), were differentiated. A flare was defined as change in DAS-28 >1.2 for RA, ASDAS ≥ 0.9 for axSpA, or clinical signs/CRP ≥ 0.5 mg/dl and/or ≥30 mm for GCA. Descriptive analyses were performed.

Results: A total of 150 patients (age 22-84 years) were included, 32 (21.3%) with a history of HZ). All received RZV at FDV, and 145 (96.7%) also at SDV. Follow-up was completed by 139 (92.7%), 129 (86%), and 100 (66.7%) patients at months 3-, 6-, and 12, respectively, with 295 vaccine doses administered. At least one AE was reported by 108, 105, 30, 22 patients at months 2, 3, 6 and 12, respectively. In total,168, 169, 33 and 25 AEs occurred at those timepoints. Most frequent localized AEs were pain at the injection site (n=102; 34.6%), swelling at the injection site (n=21; 7.1%), and redness at the injection side (n=20; 6.8%). Common systemic AEs included fever (n=49; 16.6%), fatigue (n=34; 11.5%) and musculoskeletal pain (n=31; 10.5%).


Patients reported 29, 20, 27, and 32 flares at SDV, months 3, 6 and 12, respectively, of which 11 (7.6%), 12 (8.6%), 12 (9.3%) and 13 (13.0%) met predefined flare criteria. Twelve severe AEs (SAEs) occurred (3 flares, 6 malignancies, 3 comorbidities). No AESIs or zoster breakthrough cases were reported.

Conclusion: RZV was well tolerated in patients with iRMD. Most adverse events occurred within a few days after vaccination. Flares were infrequent, and SAEs, including malignancies were considered unrelated. No AESIs or zoster cases were reported. These findings provide reassurance for both rheumatologists and prospective vaccine recipients. They support confidence in RZV safety in this population.